I have a friend who has just started his commercial diving training and
am myself in the process of upgrading my certifications to become an
instructor.  According to the research that I did for my friend the
actual SCUBA training for a commercial diver is fairly limited and
particularly focussed on aspects of SCUBA tha apply to commercial work.
Unfortunately their appears to be a significant difference in this
training and that for recreational divers.  Depending on the flavor of
your open water cert. you may actually have to re-cert in a more
accepted program before you become eligible to advance on the instructor
road.  Provided that your cert is acceptable you will have to get an
advanced cert card, be CPR and first aid certified, get a rescue diver
cert, get some form of divemaster, or assistant instructor cert (this is
agency dependent on which type of cert you need), and then you have to
get your instructor cert.  That actually may not be the end as you may
have to take advanced or specialy instructor certs before you can teach
the combination of courses you desire.
All is not bleak in OZ however as the theoretical training received in
commercial diving can prepare you very well for some of the aspects of
instructor training.  On the down side there may be a set of aquatic
skills that are taught within the recreational diving community that are
not taught for commercial SCUBA ratings.  You can ask the different
agencies if they will apply whatever you have as equivelent to some
higher level of training but it does not look to hopeful from the info
that I received.  There are a couple of PADI facilities in your area,
the NAUI organization may or may not sponsor leadership training through
a facility near you(the only NAUI affiliated instructor schools that I
know of are in Florida and California), and the YMCA organization may or
may not(depending on the location of their training facility for your
area) be conveniently located for you.  I don't really know about the
training offered by any of the other agencies in any great detail.
The least time that I have found for open water to instructor is about
two weeks from the NAUI facility in Marathon, Florida.  Last I knew the
cost for such a program was significantly more tha a couple of thousand
though.  Depending on what you need for teaching aids and such you can
expect it to run at least three times that or more.  I am skewing this
statement somewhat to the low side as I don't know what kind of "deal"
you may be able to encounter.  You also may need to prchase some
additional equipment to meet the standards for the rec SCUBA programs.
Most agencies require instructors to pay a membership fee and provide
insurance each year.  The fees and insurance vary a little bit from
agency to agency but the two fess tend to level out to around $600.00 a
year or less.
Hope this helps.  Sorry about the typos but its early yet and my fingers
aren't really awake.
Be wet and well.
Dennis
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